1. Field of the Invention
This invention relates to a washing fluid reservoir for a motor vehicle.
It relates more particularly to a reservoir for washing fluid that is to be sprayed onto windows or lights of a motor vehicle, of the type that is equipped with a vertical extension partition that divides the reservoir into a first chamber that comprises a fluid fill orifice in its upper part and a second chamber that comprises a pumping orifice in its lower part, whereby said second chamber has a wall that is common with a heating element, whereby said second chamber extends at least partially around said heating element so as to ensure the heating of the fluid that is contained in said second chamber, whereby said first and second chambers communicate with one another via a communicating orifice in the lower part of said partition so as to allow the filling of said second chamber from said first chamber.
2. Description of the Related Art
In a conventional manner, the spraying of the washing fluid onto the windshield or the lights of the vehicle is ensured by one or more spraying elements of the nozzle type, supplied with washing fluid by a feed pump from a reservoir that contains washing fluid. The washing fluid usually consists of a mixture of water and alcohol in a high proportion. Despite the presence of alcohol, the quality of washing remains mediocre.
To improve the quality of washing, it is known to heat the washing fluid. The heating of the washing fluid also makes it possible to reduce the proportion of alcohol in the mixture and thus to contribute to the preservation of the environment.
As the patent FR 2 884 477 mentions, window-washing devices in which the heating of the washing fluid is carried out by means of heating electrical resistors are known, placed at various locations in the washing circuit (see the Patents FR 2 855 079, FR 2 763 549, EP 0 456 934, FR 2 419 849 and US 2002/0134857). The presence of electrical resistors increases the energy consumption of the vehicle and requires an additional component.
An advantageous solution that avoids both additional energy consumption and the addition of other components is described in particular in the French patent application FR 2 609 437 and the German patent application DE 37 04 325. The patent applications FR 2 609 437 and DE 102005058513 propose a washing fluid reservoir that is heated upon contact with a duct that conveys a hot fluid. These solutions are not very effective in terms of heating. DE 37 04 325 proposes a washing fluid reservoir whose heating means comprise a common wall, forming a heat-exchange surface, between the washing fluid reservoir and an expansion receptacle or a box for degassing a coolant circuit of the heat engine of the vehicle.
The patent application FR 2 884 477 considers this solution in which the washing fluid reservoir and the expansion receptacle are juxtaposed to be unsatisfactory because the heat-exchange surface between the coolants and the washing fluids is limited to a single lateral face of the expansion receptacle and proposes integrating, for the most part, the expansion receptacle inside the reservoir so as to increase the heat-exchange surface between the coolants and washing fluids. This latter solution, if it allows satisfactory heating of the window-washing fluid, presents the drawback of impairing the rise in temperature of the cooling circuit fluid due to significant heat losses at the degassing box to the fluid reservoir.
Another solution in which calories that are necessary to the elevation of the temperature of the washing fluid contained in a reservoir of the vehicle housed in the engine compartment of this vehicle are sampled from the degassing box or expansion receptacle of its cooling circuit is described in the French patent application FR 2 875 763. In this solution, the reservoir at least partially surrounds the degassing box by providing between them a separation space of determined thickness in which is integrated a double-partition hollow element that delimits a thermal insulating volume that is closed on itself.
The purpose of this solution is to ensure that the sampling of calories is done under particular conditions preventing the inherent temperature of the degassing box from undergoing sudden variations with the negative impact that can arise therefrom on the proper operation of the engine.